EnviroNearby

Forrest County, Mississippi air quality history

Daily Air Quality Index summaries from EPA monitors in Forrest, Mississippi, 1999–2025.

62%
Good days in 2025
45
Median daily AQI, 2025
0
Days above 100 in 2025
363
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Forrest, Mississippi on 363 days. 226 of those days (62%) were in the Good range, and the median daily AQI was 45. That median is about the same as the typical monitored county in Mississippi (median 43 across 10 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 363 days. Across the years with fuller monitoring, the share of Good days rose: an average of 28% in 2001–2008 versus 53% in 2023–2025.

Years with fewer than 120 monitored days (2003, 2005, 2006, 2007, 2009, 2010…) are shown in the table but left out of comparisons and trend statements.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Share of monitored days in each AQI category, by year0%25%50%75%100%1999: Good 10 of 98 days1999: Moderate 86 of 98 days1999: Unhealthy for Sensitive Groups 2 of 98 days19992000: Good 24 of 119 days2000: Moderate 94 of 119 days2000: Unhealthy for Sensitive Groups 1 of 119 days2001: Good 35 of 122 days2001: Moderate 87 of 122 days20012002: Good 24 of 118 days2002: Moderate 94 of 118 days2003: Good 27 of 118 days2003: Moderate 89 of 118 days2003: Unhealthy for Sensitive Groups 2 of 118 days20032004: Good 30 of 120 days2004: Moderate 89 of 120 days2004: Unhealthy for Sensitive Groups 1 of 120 days2005: Good 24 of 109 days2005: Moderate 81 of 109 days2005: Unhealthy for Sensitive Groups 3 of 109 days2005: Unhealthy 1 of 109 days20052006: Good 26 of 118 days2006: Moderate 92 of 118 days2007: Good 27 of 114 days2007: Moderate 87 of 114 days20072008: Good 35 of 120 days2008: Moderate 85 of 120 days2009: Good 37 of 118 days2009: Moderate 81 of 118 days20092010: Good 35 of 115 days2010: Moderate 80 of 115 days2011: Good 79 of 298 days2011: Moderate 219 of 298 days20112012: Good 123 of 282 days2012: Moderate 159 of 282 days2013: Good 182 of 361 days2013: Moderate 178 of 361 days2013: Unhealthy for Sensitive Groups 1 of 361 days20132014: Good 160 of 361 days2014: Moderate 201 of 361 days2015: Good 177 of 354 days2015: Moderate 177 of 354 days20152016: Good 212 of 336 days2016: Moderate 124 of 336 days2017: Good 207 of 350 days2017: Moderate 143 of 350 days20172018: Good 195 of 359 days2018: Moderate 163 of 359 days2018: Unhealthy for Sensitive Groups 1 of 359 days2019: Good 210 of 358 days2019: Moderate 148 of 358 days20192020: Good 196 of 361 days2020: Moderate 165 of 361 days2021: Good 178 of 363 days2021: Moderate 185 of 363 days20212022: Good 178 of 365 days2022: Moderate 186 of 365 days2022: Unhealthy for Sensitive Groups 1 of 365 days2023: Good 145 of 365 days2023: Moderate 220 of 365 days20232024: Good 202 of 362 days2024: Moderate 159 of 362 days2024: Unhealthy for Sensitive Groups 1 of 362 days2025: Good 226 of 363 days2025: Moderate 137 of 363 days2025
  • Good
  • Moderate
  • Unhealthy for Sensitive Groups
  • Unhealthy
  • Very Unhealthy
  • Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median and 90th-percentile daily AQI, by year0501001999: 90th percentile AQI 842000: 90th percentile AQI 792001: 90th percentile AQI 772002: 90th percentile AQI 722003: 90th percentile AQI 792004: 90th percentile AQI 782005: 90th percentile AQI 822006: 90th percentile AQI 762007: 90th percentile AQI 792008: 90th percentile AQI 742009: 90th percentile AQI 662010: 90th percentile AQI 682011: 90th percentile AQI 682012: 90th percentile AQI 632013: 90th percentile AQI 622014: 90th percentile AQI 602015: 90th percentile AQI 592016: 90th percentile AQI 582017: 90th percentile AQI 592018: 90th percentile AQI 622019: 90th percentile AQI 602020: 90th percentile AQI 632021: 90th percentile AQI 602022: 90th percentile AQI 642023: 90th percentile AQI 682024: 90th percentile AQI 632025: 90th percentile AQI 591999: Median AQI 642000: Median AQI 592001: Median AQI 572002: Median AQI 582003: Median AQI 592004: Median AQI 562005: Median AQI 582006: Median AQI 582007: Median AQI 582008: Median AQI 562009: Median AQI 542010: Median AQI 552011: Median AQI 552012: Median AQI 522013: Median AQI 502014: Median AQI 522015: Median AQI 512016: Median AQI 462017: Median AQI 462018: Median AQI 492019: Median AQI 462020: Median AQI 482021: Median AQI 512022: Median AQI 512023: Median AQI 532024: Median AQI 472025: Median AQI 4519992001200320052007200920112013201520172019202120232025
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2025

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

PollutantDays as main pollutantShare of monitored days
Fine particles (PM2.5)363100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20253632261370000455997PM2.5
202436220215910004763103PM2.5
20233651452200000536894PM2.5
202236517818610005164105PM2.5
20213631781850000516093PM2.5
20203611961650000486397PM2.5
20193582101480000466077PM2.5
201835919516310004962119PM2.5
20173502071430000465977PM2.5
20163362121240000465874PM2.5
20153541771770000515978PM2.5
20143611602010000526076PM2.5
201336118217810005062107PM2.5
20122821231590000526376PM2.5
2011298792190000556891PM2.5
201011535800000556879PM2.5
200911837810000546691PM2.5
200812035850000567499PM2.5
200711427870000587993PM2.5
200611826920000587696PM2.5
2005109248131005882156PM2.5
2004120308910005678101PM2.5
2003118278920005979108PM2.5
2002118249400005872100PM2.5
200112235870000577793PM2.5
2000119249410005979115PM2.5
199998108620006484124PM2.5

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

Counties in Mississippi with a similar median AQI in 2025

All monitored counties in Mississippi

Source: U.S. EPA AirData, “Annual AQI by County” files for 1999–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem